The present invention relates to a device for spacing apart, exactly by the desired (and variable) lengths, the refrigerating plates of the so-said "horizontal plate" freezers.
It is known that in the freezers of such type there is a set of parallel, horizontal plates on which the (alimentary) products are placed.
Means are provided for producing cold inside the plates, i.e., these latter are cooled to a low temperature, determined according to the use requirements.
All horizontal-plate freezers for deep-freezing packed alimentary products use, as the principle for the transmission of cold, the "direct contact" between the cold plates and the product: i.e., the heat is transmitted by conduction.
When the product is inserted between two cold plates, and is in contact with them, a double heat transmission occurs thanks to the "double contact".
In order to practically embody the above principle, the plate freezers are all structured in such a way that, when they operate, in a first step the plates are "opened" (i.e., sufficiently spaced apart from each other) for the introduction of the product, and in the subsequent step they are "closed again" (i.e., approached to the product), to accomplish the "double contact".
All horizontal-plate freezers, in order to properly use the "double-contact", have their cold plates provided with spacers of the proper height, either fixed or adjustable, housed in the nearby of their outer edge, so that, in their closed position, said plates will be correctly placed parallel to one another, and in contact with the product, without damaging it.
It is clear that the use of improper spacers causes drawbacks to this type of deep-freezing, in that if they are higher than the product to be deep-frozen, a reduced heat transmission occurs (loss of the double contact), and, on the contrary, the damaging occurs of the packed articles if they are lower than them.
A normal and frequent need is, hence, for the users of said machines, changing the height of the spacers and conforming it to the packages to be deep-frozen. Said operation requires presently a considerable time, because the solution, always adopted by the designers for the purpose of fastening the spacers to the plates, has been of housing them inside seats provided on the upper face of the plates. These seats, during the weekly cycles of freezer cooling and defrosting, are filled with water which, during the cooling step, freezes, sealing and sticking the spacer inside the same seat wherein it is located, rendering it irremovable.
As a result, the operation of "replacement or adjustment of the spacers" obliges the user to defrost the freezer to unstick the spacers from the seats inside which they are inserted, and also obliges him to previously unload the product contained inside the machine, in order to prevent it from being heated. Thus, not only both of said operations must be carried out, but they cannot be carried out at the same time, resulting in a considerable time waste.
When the operation on the spacers can be combined with freezer cleaning operations, in general every 10 days, a defrosting operation is anyway carried out. In this case, the adaptation of the spacers does not cause time losses besides those strictly necessary to carry out the replacement.
But nowadays the industries tend to immediately adjust their production of deep-frozen foodstuffs to the demand by the market, which is variable, and tend to store as little as possible, so that they are obliged to change the type of product to be deep-frozen on a same freezer also twice a day.
It is in these cases that the solutions of the prior art, which require even 3-4 hours to be performed, result in large production losses.